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What is the reason for having '//' in Python? [duplicate]
...ement Alex's response, I would add that starting from Python 2.2.0a2, from __future__ import division is a convenient alternative to using lots of float(…)/…. All divisions perform float divisions, except those with //. This works with all versions from 2.2.0a2 on.
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Loop through all nested dictionary values?
...ack edge
/ \ |
_key1 __key2__ |
/ / \ \ |
|->key1.1 key2.1 key2.2 key2.3
| / | |
| value1 value2 |
| |...
Regular expression for first and last name
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79
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Convert a list of data frames into one data frame
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Use bind_rows() from the dplyr package:
bind_rows(list_of_dataframes, .id = "column_label")
share
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improve this answer
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String comparison using '==' vs. 'strcmp()'
...67122 seconds === with non-matching strings took 0.057305 seconds snipplr.com/view/758
– user503853
Apr 22 '13 at 17:00
3
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Move capture in lambda
...e following will be legal code in C++14:
using namespace std;
// a unique_ptr is move-only
auto u = make_unique<some_type>( some, parameters );
// move the unique_ptr into the lambda
go.run( [ u{move(u)} ] { do_something_with( u ); } );
But it is much more general in the sense that cap...
When should I write the keyword 'inline' for a function/method?
...hether you ask for it or not.
As an aside to prevent inlining in GCC, use __attribute__(( noinline )), and in Visual Studio, use __declspec(noinline).
Does it matter if an application is multithreaded when one writes 'inline' for a function/method?
Multithreading doesn't affect inlining in any...
Why do I get AttributeError: 'NoneType' object has no attribute 'something'?
...
Consider the code below.
def return_something(someint):
if someint > 5:
return someint
y = return_something(2)
y.real()
This is going to give you the error
AttributeError: 'NoneType' object has no attribute 'real'
So points are as below.
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How to convert a std::string to const char* or char*?
...hat needs const char* you can use
std::string str;
const char * c = str.c_str();
If you want to get a writable copy, like char *, you can do that with this:
std::string str;
char * writable = new char[str.size() + 1];
std::copy(str.begin(), str.end(), writable);
writable[str.size()] = '\0'; // ...
Why are Perl 5's function prototypes bad?
...eUploader: {
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